Laser gyroscopic systems are known which employ spliced optical-fiber rings selectively excitable in the clockwise and the counterclockwise resonant modes and operative to provide a signal indication of the rate of angular rotation of a gyro platform. In many applications, such laser gyroscopes are called upon to provide an extremely sensitive signal indication of the angular-rotation rate. In these instances, the spliced optical-fiber resonant-rings provide clockwise and counterclockwise resonant modes having wider than desirable linewidths which limits the angular-rotation rate resolution capability and thereby their utility.